1. Field of the Invention
The present invention relates to an output apparatus for receiving code data from a data source of a host computer or the like and developing into pattern data and outputting.
2. Description of the Related Background Art
In a conventional printer for printing by a dot matrix, a character code or the like which is output from a host computer or the like is input, pattern data corresponding to the character code is read out of a character pattern generator and developed as image data into a frame memory or the like, and thereafter, the image data is output to a recording section of a printer and recorded onto a recording medium. The character pattern data stored in such a character pattern generator can be mainly classified into the following three kinds.
1 A dot matrix pattern to express a character pattern (hereinafter, referred to as a dot matrix font) PA1 2 A font in which an outline or stroke of a character is expressed by coordinate points for an origin of the character (hereinafter, referred to as a vector font) PA1 3 A font in which a dot matrix pattern is compressed by some compressing technique (for instance, run length or the like) and constructed (hereinafter, referred to as a compression font)
Among those font data, the dot matrix font can be easily pattern developed into a frame buffer. However, since it is unsuitable for a modification of a character or the like, the use of the vector font which can easily cope with the rotation, enlargement, reduction, etc. of a character has been increasing more and more. On the other hand, as a resolution of output apparatus becomes high, a font capacity increases. To cope with it, a compression font is used. Further, in recent years, a mixed type in which the vector font and compression font are combined has been also proposed. Assuming that the above fonts are generally referred to as "nondot matrix type fonts", although the nondot matrix type fonts have advantages which cannot be obtained by the dot matrix font, they have a problem such that it takes a longer time to develop a pattern into an image memory or the like as compared with the simple dot matrix type font.
To solve such a problem, there is a font cache method. According to the font cache method, when a nondot matrix type font is developed into an image buffer or the like, font data or the like whose use frequency is high is previously developed into the dot matrix type font and stored into a cache memory (RAM), and when developing into image data, by using the pattern data, a whole processing speed is improved.
In a printer or the like having such a font cache, in association with a variation of a print output, before print data is output from a host computer, font data, auxiliary font data, form data (pattern such as a background of each page or the like), etc. which have previously been formed by the user can be downloaded and registered. The downloaded data is ordinarily stored into a fixed area in the font cache. Therefore, even if the downloading function is not used, a size of font cache is limited. On the contrary, in spite of the fact that a font data amount in the font cache is small, an amount of font data or the like to be downloaded is limited.